Spun-bonded nonwoven webs are important articles of commerce for use in consumer and industrial end uses. Such products commonly possess a textile-like hand and appearance and are useful as a component of disposable diapers, in automotive applications, and in the formation of medical garments, home furnishings, filtration media, carpet backings, fabric softener substrates, roofing felts, geotextiles, etc.
In accordance with the technology of the prior art, a molten melt-processable thermoplastic polymeric material is passed through a spinneret to form a multifilamentary fibrous spinline, is drawn in order to increase tenacity, is passed through a quench zone wherein solidification occurs, is collected on a support to form a web, and is bonded to form a spun-bonded web. The drawing or attenuation of the melt-extruded spinline has been accomplished in the past by passage through a pneumatic forwarding jet or by wrapping about driven draw rolls. An apparatus arrangement utilizing both draw rolls and gas flow is disclosed in U.S. Pat. No. 5,439,364. The equipment utilized for spun-bonded nonwoven production in the past commonly has necessitated relatively high capital expenditures, multiple spinning positions, large volumes of air, and/or has presented denier variability shortcomings when one is interested in the expeditious formation of a nonwoven product on an economical basis.
It is an object of the present invention to provide an improved process for the formation of a spun-bonded web.
It is an object of the present invention to provide a process for the formation of a spun-bonded web that can be carried out on an expeditious basis to form a substantially uniform product having a satisfactory balance of properties.
It is an object of the present invention to provide a process for the formation of a spun-bonded web that is relatively user friendly and offers the ability to routinely produce a quality nonwoven product in the substantial absence of deleterious roll wraps.
It is an object of the present invention to provide an improved process for the formation of a spun-bonded web wherein the spinline is capable of undergoing self-stringing and requires minimal operator intervention.
It is an object of the present invention to provide improved technology that is flexible with respect to the chemical composition of the melt-processable thermoplastic polymeric material that serves as the starting material.
It is an object of the present invention to provide a process that is capable of producing with good denier control a substantially uniform light weight spun-bonded product at relatively high spinning speeds on a reliable basis.
It is another object of the present invention to provide an improved process for the formation of a spun-bonded web while making possible a reduced capital expenditure as well as reduced operating expenditures.
It is yet another object of the present invention to provide a process for forming a spun-bond web wherein reduced operating expenses are possible with respect to air-flow requirements when compared to technology of the prior art involving the use of an air forwarding jet to accomplish attenuation.
It is a further object of the present invention to provide an improved apparatus for the formation of a spun-bonded web.
These and other objects, as well as the scope, nature, and utilization of the invention will be apparent to those skilled in nonwoven technology from the following detailed description and appended claims.